Warming: Storm damage ahead

Hurricane season may still be months away, but the threat of flooding is already on the rise in Maryland, as documented by the latest reports on climate change released this week. Rising sea levels have raised the risk of coastal flooding, particularly from severe storms.

Analyzing both the latest forecasts of rising high tides caused by warming oceans and the latest population data from the 2010 census, one of several studies released this week, "Surging Seas" by scientists associated with the nonprofit Climate Central environmental research organization, found 3.7 million Americans living near the water will be at risk in the coming decades.

Maryland is relatively high on that list, with Ocean City and nearby Ocean Pines rated as particularly vulnerable, followed by waterfront communities from Crisfield on the Eastern Shore to Shady Side in Anne Arundel County and waterfront Baltimore. In all, some 40,000 homes located five feet or less above high tide are considered to be under the greatest threat.

The danger is that 100-year-floods — considered so rare that they might appear once every hundred years — will become much more commonplace. The odds of such a flood at Fort McHenry, for instance (involving a at least a 13-inch storm surge), are a mere 1-in-4 chance by 2030, researchers estimate.

Such storms could produce damage similar to a tsunami, especially in low-lying coastal Worcester County where damage to Ocean City's high-rises, boardwalk and vacation property could be extreme. In essence, what would otherwise have been a once-in-a-century storm could become a once-in-300-years storm that would lay waste to billions of dollars of investment.

This isn't the first time that scientists have documented U.S. vulnerability to rising sea levels, a trend that has been going on for more than a century. Insurance companies have already taken note, and many are no longer offering flood insurance.

While the timetable and specifics are subject to debate, there is no serious doubt about the consensus scientific view that ocean levels are rising because of man-made climate change, and coastal communities are threatened by it. Whether sea levels rise by three feet or four feet, coastal towns and cities are in danger when major storms strike, as they inevitably will.

Yet much of the nation's leadership appears to be largely in denial, with Republicans especially keen on laughing off a danger so clear that U.S. insurance companies won't go near it. GOP presidential candidate Rick Santorum recently called climate change a "myth" even as he was campaigning in Biloxi, Miss., a coastal community that has seen its share of devastating floods.

President Barack Obama has done better pursuing policies to improve automobile fuel efficiency, promote green energy, reduce power plant emissions and negotiate international agreements to limit greenhouse gas emissions, but it's hardly been his highest priority in office. During January's State of the Union address, the president mentioned climate change just once, and that was to note that Congress was too divided to deal with the issue right now.

Will it take a major disaster to strike before Americans demand more from Washington on global warming? If so, such action may come too late — at least for those living anywhere near the water. Once glaciers melt and ocean waters warm and expand, the genie can't be put back in the proverbial bottle.

Marylanders ought to be setting an example, not just in reducing harmful emissions but in preparing for the worst-case scenarios. That can start by banning new development in the 100-year flood plain. The last thing the government should be doing is subsidizing people's decisions to live in high-risk locations, which is exactly what the federal government's flood insurance program does.

This isn't a problem that can be solved overnight but will take decades to address. That's not cause for delay but reason to do more now, as the window for affecting climate change is gradually closing, whether deniers like Mr. Santorum will acknowledge it or not.

When the floods do come, the victims may look back and wonder why an earlier generation did so little to prevent such catastrophe. What will we tell them? Surely not that we didn't see it coming, but perhaps we'll just have to admit that we did — and chose to do nothing anyway.